Heat of 30 kcal is supplied to a system and 4200 J of external work is done on the system so that its volume decreases at constant pressure. What is the change in its internal energy ? (J=4200 J/kcal)
47,057 results
(28) Chemistry  Science (Dr. Bob222)
Which of the following statements is correct? A) The internal energy of a system increases when more work is done by the system than the heat that flows into the system. B) The system does work on the surroundings when an ideal gas expands against a

Honors Chemistry
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Physics
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Science
In a heat engine, if 700 J of heat enters the system, and the piston does 400 J of work, what is the final internal (thermal) energy of the system if the initial energy is 1,200?

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How many calories must be supplied to 59 g of ice at −6 C to melt it and raise the temperature of the water to 61 C? The specific heat of ice is 0.49 kcal/kg · K and of water is 1 kcal/kg · K; the heat of fusion of water is 79.7 kcal/kg, and its heat

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When 1.0 mole of liquid Br2 is converted to Br2 vapour at 25.0oC and 1.0 atm pressure, 7.3 Kcal of heat is absorbed, and 0.59 kcal of expansion work is done by the system. Calculate ΔU for this process

alaqsa
When 1.0 mole of liquid Br2 is converted to Br2 vapour at 25.0oC and 1.0 atm pressure, 7.3 Kcal of heat is absorbed, and 0.59 kcal of expansion work is done by the system. Calculate ΔU for this process

Physicsl Science
A heat pump releases 103.0 kcal as it removes 54.0 kcal at the evaporator coils. how much work does this heat pump ideally accomplish? Answer should be in KJ

physics
an electric heater raises the temperature of 120g of water in a thin light vessel through 10K in 2mins, when placed in 70g of water contained in a metal vessel of mass 0.55kg the temperature rises through 9K in the same time. Calculate from the above:

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CORRECTION N2 + O2 > 2 NO change in heat (delta H)= 43.2 kcal based on the reaction, which statement is true? a) 43.2 kcal are consumed when 1.00g of O2 reacts b) 43.2 kcal are consumed when 1.00g of N2 reacts c) 43.2 kcal are consumed when 1.00g of NO

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(a) How much heat in kcal must be provided for a 0.853 kg block of lead to raise the temperature of 0.015 kg block of ice from 5ºC to 0ºC? (b) How much heat in kcal must be provided for a 0.853 kg block of lead to melt a 0.015 kg block of ice from at

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Potassium nitrate has a lattice energy of 163.8 kcal/mol and a heat of hydration of 155.5 kcal/mol. How much potassium nitrate has to dissolve in water to absorb 107 kJ of heat?

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Physics
Heat of 30 kcal is supplied to a system and 4200 J of external work is done on the system so that its volume decreases at constant pressure. What is the change in its internal energy ? (J=4200 J/kcal)

Physics
Heat of 30 kcal is supplied to a system and 4200j of external work is done on the system so that it's volume decreases at constant pressure.what is the change in its internal energy (J=4200 j/kcal)

chemistry
N2 + O2 > 2 NO change in heat (delta H)= 43.2 kcal based on the reaction, which statement is true? a) 43.2 kcal are consumed when 1.00g of O2 reacts b) 43.2 kcal are consumed when 1.00g of N2 reacts c) 43.2 kcal are consumed when 1.00g of NO is produced

physical science
Lead is a soft, dense metal with a specific heat of 0.028 kcal/kg·C°, a melting point of 328.0°C, and a heat of fusion of 5.5 kcal/kg. How much heat must be provided to melt a 202.2 kg sample of lead with a temperature of 20.0°C?

Chemistry
Hi! I have another question. So 1 kcal of heat is added to 1.5 L of oxygen in a container at constant pressure. (1atm). Then volume increases to 3.1L. they want to know total energy change. Now i think the formula is DH=DU + PDV so what i did was DH = 1

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chemistry help!
Potassium nitrate has a lattice energy of 163.8 kcal/mol and a heat of hydration of 155.5 kcal/mol. How much potassium nitrate has to dissolve in water to absorb 105 kJ of heat?

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1. What is the change in internal energy (in J) of a system that absorbs 0.677 kJ of heat from its surroundings and has 0.438 kcal of work done on it? 2. A 30.5 g sample of an alloy at 94.0°C is placed into 48.7 g water at 20.3°C in an insulated coffee

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How do I determine the value of the reaction 2HI(g) + 2.4 kcal > H2(g) + i2(g) delta H = a) 2.4 kcal b) 2.4 kcal c) 0.00024 kcal d) 0.00024 kcal

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In a heat engine, if 700 J of heat enters the system, and the piston does 400 J of work, what is the final internal (thermal) energy of the system if the initial energy is 1,200 J?

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How much heat must be removed from a 200 g block of copper to lower its temperature from 302 oF to 68 oF? Specific heat of copper: c = 0.092 kcal/(kg K) a. 2.4 kcal b. 2400 kcal c. 18.4 kcal d. 12 kcal e. 26 kcal

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An electric heater raises the temperature of 120g of water in a thin light vessel through 10K in 2mins, when placed in 70g of water contained in a metal vessel of mass 0.55kg the temperature rises through 9K in the same time. Calculate from the above:

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Chemistry
What is the change in internal energy (in J) of a system that absorbs 0.677 kJ of heat from its surroundings and has 0.438 kcal of work done on it?

Chemistry
What is the change in internal energy (in J) of a system that absorbs 0.677 kJ of heat from its surroundings and has 0.438 kcal of work done on it?

Chemistry
What is the change in internal energy (in J) of a system that absorbs 0.677 kJ of heat from its surroundings and has 0.438 kcal of work done on it?

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A heat engine absorbs 126 kcal of heat and exhausts 77 kcal of heat in each cycle. Calculate the efficiency (as a percentage)

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A heat engine absorbs 126 kcal of heat and exhausts 77 kcal of heat in each cycle. Calculate the efficiency (as a percentage)

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A heat engine absorbs 126 kcal of heat and exhausts 77 kcal of heat in each cycle. Calculate the efficiency (as a percentage)

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Hi! I have another question. So 1 kcal of heat is added to 1.5 L of oxygen in a container at constant pressure. (1atm). Then volume increases to 3.1L. they want to know total energy change. Now i think the formula is DH=DU + PDV so what i did was DH = 1

Chemistry
Hi! I have another question. So 1 kcal of heat is added to 1.5 L of oxygen in a container at constant pressure. (1atm). Then volume increases to 3.1L. they want to know total energy change. Now i think the formula is DH=DU + PDV so what i did was DH = 1

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How much (in Celsius degrees) is the temperature of 1.3 kg of alcohol raised by adding 4.1 kcal of heat? The following piece of information may come in handy: specific heat of alcohol is 0.58 kcal/kgC.

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How much (in Celsius degrees) is the temperature of 1.3 kg of alcohol raised by adding 4.1 kcal of heat? The following piece of information may come in handy: specific heat of alcohol is 0.58 kcal/kgC.

physics
lead is a soft, dense metal with a specific heat of 0.028 kcal/kg degrees C, a melting point of 328.0 degrees C and a heat of fusion of 5.5 kcal/kg. How much heat must be provided to melt a 250.0 kg sample of lead with a temperature of 20.0 degrees

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Potassium has a lattice energy of 163.8 kcal/mol and a heat of hydration of 155.5 kcal/mol. How much potassium nitrate needs to dissolve in water to absorb 114 kJ of heat?

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Potassium has a lattice energy of 163.8 kcal/mol and a heat of hydration of 155.5 kcal/mol. How much potassium nitrate needs to dissolve in water to absorb 114 kJ of heat?

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Chemistry
Gasoline, which can be represented by the formula octane, bulk density is 704 g/l. To estimate the variation in enthalpy when burning 28.5 liters gasoline, based on the binding energies: 0 = 0 (117 kcal); C = 0 (173 kcal); 0 h (111 kcal); CC (83 kcal);

Chemistry
Gasoline, which can be represented by the formula octane, bulk density is 704 g/l. To estimate the variation in enthalpy when burning 28.5 liters gasoline, based on the binding energies: 0 = 0 (117 kcal); C = 0 (173 kcal); 0 h (111 kcal); CC (83 kcal);

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The petrol, can be represented by the formula of the octane rating, has earth specifies 704 g/L. Estimate the enthalpy variation when burning 28.5 liters of petrol, assuming energies of connection 0 = 0 (117 kcal) C = 0 (173 kcal) 0–H (111 kcal) C–C

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physics response to bobpursley
which is false? Consider the following processes: I. Energy flows as heat from a hot object to a colder object II. Work is done on a system and an equivalent amount of energy is rejected as heat by the system III. Energy is absorbed as heat by a system and

chem
Potassium nitrate has a lattice energy of 163.8 kcal/ mol and a heat of hydration of 155.5 kcal/ mol . How much potassium nitrate has to dissolve in water to absorb 105kj of heat? Answer in kg.

chemistry
Potassium nitrate has a lattice energy of 163.8 kcal/mol and a heat of hydration of 155.5 kcal/mol. How much potassium nitrate has to dissolve in water to absorb 114 kj of heat?

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abiapoly heat energy
500g of copper is heated from 30 degree celcius to 120 degree celcius what is the quantity of heat supplied b.if the same quantity of heat is supplied to 300g of water initial at 30degree what will be the final temperature?

Chemistry
How do I determine the value of the reaction 2HI(g) + 2.4 kcal > H2(g) + i2(g) delta H = a) 2.4 kcal b) 2.4 kcal c) 0.00024 kcal d) 0.00024 kcal

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phyics
during a process, 21.6 MJ of heat is added to closed system. if the internal energy is increased by 59.6 MJ, how much work in Btu was done? is the work done on ro by the system?

Heat energy
CORRECTION (a). 500g of copper is heated from 30 degree celcius to 120 degree celcius, what is the quantity of heat supplied?(b). If the same quantity of heat is supplied to 300g of water initial at 30 degree celcius. What will be the final temperature.